Temporary pacing wires are placed at almost every cardiac operation, but there have been no advances for many years. There are a number of current temporary pacemaker leads available for pacing after cardiac surgery. Leads (in reality a bare segment of an insulated wire) can be attached to the heart by a suture which holds the exposed wire in contact with the surface of the heart. When the lead is removed it is simply pulled out, breaking the stitch. The other way to attach the temporary lead is to attach a needle to the end of it and then pass the needle through the heart with a partial thickness bight. The needle is then cut off the wire. Exposed wire is left in contact with the heart. The wire is removed by simply pulling it out. The wire often has a series of bends or a small amount of attached plastic material to increase the friction to keep it from coming out.
There are a number of problems with these two options. Referring to FIG. 1, the suture method requires that the surgeon place a stitch in the form of a loop 10 and then feed the wire 12 through the loop 10 and tie it. This is somewhat tedious, especially on a beating heart 14. The wire 12 under the suture loop to is often easily removed by even a minimum of pull on the wire and it frequently has to be replaced. When a secure wire 12 is removed, there is the risk that the surface of the heart 14 will be torn as the suture snaps or that the suture does not snap and a small divot 16 of myocardium is pulled off as also shown in FIG. 1. This can lead to bleeding which can be fatal.
The second system is shown in FIG. 2 whereby a wire suture 20 is passed through the heart 14 is quicker. The wire suture 20 must be passed and the wire cut off as shown at cut 22 located above a flared stop portion 24. Flared stop portion 24 is designed to prevent the wire from being pulled back through heart 14. However, during insertion the wire 20 frequently causes bleeding and the bleeders must be sutured. When the wire 20 is removed, there is a risk that the friction of the wire removal combined with the drag of the flared portion 24 will result in a piece of myocardium being torn, again resulting in bleeding. Also, the wire 20 frequently becomes dislodged before the chest is closed and it has to be replaced.
The prior art does not demonstrate the concept of leaving a small permanent electrode in place and separating this from the wire. This concept is very important because on removal the risk of bleeding comes when the wire is pulled through the heart muscle or when the suture must snap.
In short, current methods are somewhat tedious, can result in bleeding at insertion and removal and the leads frequently become dislodged requiring complete reinsertion. It would be very useful to ease the insertion, permit reattachment should the wire become dislodged and reduce the risk of bleeding when the wire is removed.